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Joined: Jul 2004
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G
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Not legally but there was not much legal in that house when I first looked at it.
Note the Romex going into that cap too.


Greg Fretwell
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This "light kit" in the fan was a classic too.

[Linked Image from gfretwell.com]


Greg Fretwell
Joined: Dec 2001
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Originally Posted by gfretwell
Oh yeah, That goes to the water heater

[Linked Image from gfretwell.com]


Isn't that actually the gas pipe coming up from the floor on the right? Or is that hot, cold and recirculation?

Would it be legal to plug in the water heater if you used a cord with proper strain relief on the water heater? Technically I can't see any reason not to, but code isn't always strictly about technical issues - technically the electrons wouldn't care if the hot wire were green.

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Tex:
That is from a 'blow-off' valve to relieve water pressure in the heater. The pipe going down extends any discharge down to the floor


John
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My earlier, flippant response failed to recognize one important thing: The OP is right.

Indeed, for nearly every sort of circuit his reasoning is absolutely correct, and the NEC is designed specifically to prevent such situations from arising. With, of course, one exception .... this specific situation.

That is, the household 'convenience circuit' is the only circuit where the demands of the applied loads are not considered. Indeed, we are exempted from even using a token load value in deciding how many receptacles to place on one circuit.

Nope. It's 'keep adding receptacles' and common sense be cast aside.

This attitude seems based upon a model that uses a completely different set of assumptions. We assume that, since we cannot know what will be used, or where it will be, that we can rely upon chance and the breaker to give adequate protection.

Let me use a little project of mine to illustrate the point:

I've been using a "Kill-A-Watt" recently to see just how much current various household appliances actually draw. (I'll start a thread when I have more data). So far, my 'ordinary' kitchen appliances are showing current draws from 2 amps (the rice cooker) to 15+ amps (the microwave). All of these appliances have standard "15 amp" plugs.

If we applied the usual NEC rules, neither extreme would be allowed on a 15-amp circuit. We would require a much smaller fuse to protect the rice cooker, and the microwave is clearly supposed to be on a 20-amp circuit.

While the NEC has made some changes that reduce the impact of these facts - kitchens are required to have at least two 20-amp circuits, the changes do not affect the underlying assumptions.

We simply don't size receptacle circuits the same way we size everything else. It has nothing to do with whatever silly things we have seen in the past.

That's why the OP became confused.

Last edited by renosteinke; 01/30/15 01:37 PM.
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OK, let's try to get back on track...
The OP is in Germany, designing a machine for the USA.

He has not made any comments to any of the responses here, as of yet.

WE all have to remember that the NEC is not a design tool, but the minimum (or maximum, in some cases).

To the 'microwave' comment from Reno...is it a dedicated circuit for the micro, on #12 & a 20 amp OCP, with a single 20 amp, 120 volt receptacle??


John
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Greg:
I saw the NM going to the cord cap, and bit my tongue on that.

I think we beat that up in another thread, along with the fan light.


John
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Dedicated circuit? Who knows? Who cares?

First, let's be sure we understand the source of my number. I took a new, ordinary, "1000 Watt" microwave, plugged it into the Kill-A-Watt, then plugged the meter in to a convenient receptacle. Put a cup of tea in the micro, push the 'cook' button, and take the reading as it ran.

I just repeated the test, and read 14.86 amps at 119,8 volts. Note that I (still) have no idea as to what the nameplate reads.

There's no code requirement for a dedicated circuit, or a 20-amp circuit, for this microwave. Anyone can plug it in anywhere. John, you're making the same error as the OP.

More germane to my post is that all those code rules about 'plug connected loads' go right out the window for convenience circuits. The rules apply to the circuit for your clothes dryer but not for any convenience circuit. Only when the circuit is dedicated to a use do they apply.

This, of course, is necessary, as we have no way of knowing what will actually go into the receptacle. Thus the NEC has us run convenience circuits in the same manner as a farmer feeds his chickens ... a few over here, some over there, and hope for the best. Lots of chickens, we say he can use a larger "20 amp" handfull laugh

Add to this the various 'engineering assumptions' of the rating labs, and that 15-a plug can very well be deliberately overloaded for brief periods. It's a safe bet that requiring 20-amp plugs on the most common microwave size would very quickly result in the 1000-watt microwave becoming extinct.


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Reno:
My error is that I thought you were talking about a 'fixed' micro, the over the range type. Sorry for that!!

Yes, 100% on people plugging in 'appliances' and reaching or exceeding the circuit capacity.

The discrepancy between the nameplate info, and your actual reading may be a marketing move by the mfg. Single items cannot exceed a percentage of the circuit capacity, without being factory marked that a dedicated circuit is required.
(think window air conditioners)



John
Joined: Dec 2001
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Originally Posted by HotLine1
Tex:
That is from a 'blow-off' valve to relieve water pressure in the heater. The pipe going down extends any discharge down to the floor

Ah, thought the fittings didn't really look like gas!

In case of the rice cooker the rationale is probably similar to what we have in Europe - if the appliance needs a fuse, it has to be built into the appliance itself and if it doesn't the appliance will limit the current under normal operating conditions in order to protect the cord. The household breaker/fuse only needs to protect the cord in case of a short. That's why you can connect a table lamp with 0.75 mm2 flex and Euro plug to a 230 V/16 A circuit.

Of course power strips with Euro plugs are illegal because they could draw well over 2.5 A from a socket only designed for that current.

Doesn't work in the UK since 32 A isn't suitable for short-circuit protection of 0.75 mm2 and BS1363 power strips aren't designed for 32 A.

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